Definition of frequency modulation in English:

noun

These data were not used to measure time lags between the acoustic and seismic channels, but merely to demonstrate the similarity in frequency modulation and duration of signals in both the air and ground.

The system can tell how tired or stressed the speaker is by detecting irregularities in frequency modulation and analysing other factors, he said.

Each frame of one of Ofer's movies shows a few thousand syllables from a given bird, plotted on a couple of dimensions such as duration and amount of frequency modulation.